The high-resolution lattice imaging technique of transmission electron microscopy has been utilized to monitor the decomposition process in Au–Ni spinodal alloys. Individual measurements were made of lattice fringe spacings which are sensitive to composition variations at the atomic plane level. The results indicate that rather smooth and regular composition waves are obtained at an early state of decomposition, and that later stage coarsening results in larger amplitude fluctuations. This provides direct evidence of simultaneous decomposition and coarsening which agrees with theoretical predictions.
An analysis of reaction kinetics and morphology suggests that the decomposition is one-dimensional, even after very long aging times. This behavior is believed to be the combined result of a large matrix strain energy associated with the decomposition product and the slow decomposition kinetics due to low temperature aging (at 423 K).

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Small-angle X-ray scattering intensity was measured for several Al–Zn alloys aged for 60 ks at various temperatures between 293 and 393 K. Scattering intensities were found to obey a scaling rule, when the alloys with the same chemical composition were aged at different temperatures. Under the present aging conditions, G.P.zones had the average radius between 1 and 2 nm, and their average nearest neighbor distance among zones lay in the range between 10 and 25 nm. Both of the size and the distance among zones were minimized at the aging temperature around 350 K in the binary Al–Zn alloys, and they became smaller and shorter with decreasing temperature in the alloys containing by 0.1 at%Mg. The dependence of the inhomogeneous structure containing G. P. zones on the alloy composition and aging temperature could be qualitatively explained in terms of diffusivity of solute atoms and coherency strain around zones. The present study established a universal method for the small-angle scattering intensity analysis to obtain the knowledge on the spatial distribution as well as the volume fraction and the size distribution of G.P.zones.

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The influences of changes in the conditions of heat treatment and cold working on the low temperature mechanical properties were studied on solution-annealed, sensitized and hydrogenated austenitic stainless steels of seven types. Principal results obtained are as follows.
(1) Austenitic stainless steels that are sensitized at 1073 K (800°C) invariably exhibit the low temperature hydrogen embrittlement when tested at 77 K (−196°C).
(2) Those stainless steels, sensitized at 1073 K (800°C) for 86.4 ks (24 h) then hydrogenated, exhibit increasing resistivity to the low-temperature hydrogen embrittlement in the sequence of 304–316–321–310=347–304L=316L, when tested at 77 K (−196°C).
(3) The range of sesitization treatment in which type 304 steel exhibits strong hydrogen embrittlement when subsequently tested at cryogenic temperatures is 923 K (650°C) to 1223 K (950°C), particularly from 1073 K (800°C) to 1173 K (900°C).
(4) Cold working tends to enhance the low-temperature hydrogen embrittlement.

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The electrical conductivity of MgS and SrS disks carefully prepared to avoid any contamination has been measured at temperatures from 973 to 1223 K and in the P_S2 range from 10⁻¹⁰ to 10⁴ Pa. Because the conductivity was independent of sulfur pressure in the low sulfer pressure range, it was concluded that MgS and SrS may be ionic conductors. The specific conductivity can be expressed as follows;
(Remark: Graphics omitted.)
and the apparent activation energy for the conduction of MgS and SrS is 218 kJ/mol and 180 kJ/mol, respectively.
However, in the high sulfur pressure range, the specific conductivity of both sulfides increases with an increase in sulfur pressure, suggesting the positive hole conduction.

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Yttrium sulfide disks have been carefully prepared by means of a newly developed sintering method to avoid any contamination. The electrical conductivity has been measured at temperatures from 973 K to 1223 K and in the P_H2S⁄P_H2 range from 10⁻⁴ to 10² with the aid of an alternating current (1 kHz) bridge. It has been concluded that yttrium sulfide is a pure electronic conductor under the above-mentioned conditions. The specific conductivity is expressed as follows;
for n-type range (Remark: Graphics omitted.)
and for p-type range (Remark: Graphics omitted.)
The observed sulfur pressure dependence is attributed to the predominance of fully ionized yttrium interstitials and fully ionized yttrium vacancies.

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The activity of Cu in solid Co for 1158≤T≤1473 K has been determined by equilibrating the surface of initially pure Co plates with liquid Ag–Cu alloys and by using the literature values of the Cu activity in Ag–Cu alloys. The equilibration has been confirmed from good agreement of surface compositions between an initially pure Co plate and a Co–Cu alloy plate having more content of Cu than the surface concentration. Equilibrated Co plates were essentially binary Co–Cu alloys, because no Ag was detected by an electron probe analyzer in the Co plates. Interdiffusivities in solid Co–Cu alloys for a temperature range of 1158≤T≤1273 K have also been determined from penetration profiles of Cu in the plates. The ternary phase diagram for the Ag–Cu–Co system has been determined from solubility measurements of Co in liquid Ag–Cu alloys.

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The equilibrium relations of constituent elements between matte and calcium ferrite slag have been studied. The experiments were carried out at 1523 K under controlled SO₂ pressure or inert gas atmosphere for the three-liquid system of metallic copper-matte-slag and the two-liquid one of matte-slag.
The experimental results of the calcium ferrite slag showed considerably different equilibrium behaviours as compared with those of the silica-saturated iron silicate slag. The contents of sulfur and copper in the calcium ferrite slag increased with decreasing copper content in matte, which is closely related to the mutual dissolution between matte and slag. Therefore, it has been concluded that the calcium ferrite slag has no advantage over the iron silicate slag for the separation of slag from matte, although the present results are quite interesting from the theoretical standpoint of mutual dissolution between matte and slag.
The distribution ratios of lead with the calcium ferrite slag were about one-tenth of those with the iron silicate slag. Thus, lead is less concentrated into the calcium ferrite slag in comparison with the iron silicate slag.

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Copper sheets recrystallized have the cubic texture {100}⟨001⟩, and this orientation becomes very sharp with increasing cold rolling reduction. This {100} orientation, however, injures the drawability of metal sheets, resulting in inferior drawability of copper sheets compared with that of other metal sheets. Cold rolled copper sheets, on the other hand, are expected to have good drawability, because they have the favourable orientation {100} for the drawability.
The present experimental results obtained from Load Deep Drawing Test verify that the copper sheets as cold rolled can be drawn successfully. The drawability decreases with increasing rolling reduction in the range of low reduction, but increases with the increase in reduction in high reduction range over 70%, reaching L.D.R. of 2.5 at 95% reduction. It is concluded that the drawability of copper sheets as cold rolled can be improved by development of the orientation {110}.

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The dry wear characteristics of chopped carbon fiber-(Al–Cu) composites containing 8.7 to 32 vol% CF produced by the powder metallurgical process were investigated by using a pin-rotating cylinder type wear test apparatus.
The wear volume of the composites was reduced to about 1/3 to 1/6 of that of sintered Al–Cu compact under loads, 0.98 N and 1.96 N, and to 2/3 to 1/3 under a higher load, 3.43 N. The reduction of the wear by introducing CF is considered to be smaller for higher contact pressures, and the wear-distance-ratio is larger for the initial stage of wear process, when the apparent contact pressure is high. These results may be due to lack of bond formation between CF and the metal matrix. The wear volume could be considered to be inversely proportional to the CF amounts, and decrease in the wear volume with increasing CF amount was much larger than the reduction of friction coefficient.
It may be presumed that the higher loading capacity of CF is rather responsible than its lower frictional characteristics for the good wear resistance of the CF–(Al–Cu) composites.

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